FAILURE DIAGNOSIS
1-142
TNV DI Service Manual
Method and Procedure of Failure Diagnosis
Work Description
1. Check of the sensor resistance value (sensor only):
• Between accelerator sensor terminals A and C (all the resistance value)
•
Remove the accelerator sensor from the harness.
•
Measure the resistance between sensor terminals A and C (all the resistance value) using a circuit tester.
(REF) Total resistance value of Yanmar standard accelerator sensors
• Between accelerator sensor terminals A and B
•
Measure the resistance between accelerator sensor terminals A and B using a circuit tester.
•
Check if the resistance value between accelerator sensor terminal A and B fluctuates when the
accelerator throttle is moved.
2. Check of the sensor resistance value ( harness):
• Between harness E38 and E28 (total resistance value)
•
Connect accelerator sensor and harness, and remove E-ECU from the harness.
•
Measure the resistance between harness side E-ECU connectors E38 and E28 (total resistance value)
using a circuit tester.
*See above-mentioned “(REF) Total resistance value of Yanmar standard accelerator sensors”.
• Between harness E38 and E28
•
Measure the resistance between E-ECU connectors E35 and E28 using a circuit tester.
•
Check if the resistance value between E-ECU connectors E35 and E28 fluctuates when the accelerator
throttle is moved.
Terminal
Specification
Sensor A - C
5 ± 1.5k
Ω
NG
Replace the accelerator sensor.
OK
Check the resistance value between accelerator sensor terminal A and B.
→
Go to
[• Between accelerator sensor terminals A and B]
NG
Replace the accelerator sensor.
OK
Check the sensor resistance with the sensor and the harness being connected.
→
Go to [2. Check of the sensor resistance value ( harness):]
NG
Check the harness for correct continuity.
→
[3. Check of harness continuity:]
OK
Check the resistance value between the harness E35 and E28.
→
Go to [• Between
harness E38 and E28]
NG
Check the harness for correct continuity.
→
[3. Check of harness continuity:]
OK
Check the sensor resistance with the sensor and the harness being connected.
→
[2. Check of the sensor resistance value ( harness):]
TNV_DI_SM_A4-Troubleshooting.book 142 ページ 2007年11月15日 木曜日 午後5時27分